Hank Greenberg, who built AIG into a financial powerhouse, has donated $10 million to the super PAC backing Republican presidential candidate Jeb Bush, making Greenberg one of the largest contributors in the 2016 race.

Some Fannie and Freddie shareholders said Monday they viewed the AIG decision as generally encouraging given what they see as the government’s less defensible approach with the mortgage-finance giants.

The nation’s biggest life insurer by assets is weighing a legal showdown with the U.S. after a panel of regulators concluded it poses significant risks to the financial system and warrants tougher oversight.